Summary of Warrants and Related Information (Detail) - Warrant	6 Months Ended
Jun. 30, 2018 $ / shares shares	Jun. 30, 2017 shares
Warrants
Outstanding	20,000
Granted	0	0
Outstanding	20,000
Exercisable at June 30, 2018	20,000
Weighted Average Exercise Price
Outstanding \| $ / shares	$ 6.64
Outstanding \| $ / shares	6.64
Exercisable at June 30, 2018 \| $ / shares	$ 6.64

Number of warrants or rights exercisable.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options weighted average exercise price.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights exercisable.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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